<template>
    <div class="todo-header">
        <input type="text" placeholder="请输入你的任务名称，按回车键确认" v-model="title" @keyup.enter="add"/>
    </div>
</template>

<script>
    import {nanoid} from 'nanoid'
    export default {
        name:'MyHeader',
        props:['addTodo'],
        data() {
            return {
                title:''
            }
        },
        methods:{
            add(){
                //校验数据
                if(!this.title){
                    alert("数据不能为空！");
                    return;
                }
                //将用户的输入包装成一个todo对象
                const todoObj={id:nanoid(),title:this.title,done:false};
                
                //通知App组件去添加一个todo对象
                this.addTodo(todoObj);
                this.title='';//清空输入
            }
        }
    }
</script>

<style scoped>
    /*header*/
    .todo-header input {
        width: 560px;
        height: 28px;
        font-size: 14px;
        border: 1px solid #ccc;
        border-radius: 4px;
        padding: 4px 7px;
    }

    .todo-header input:focus {
        outline: none;
        border-color: rgba(82, 168, 236, 0.8);
        box-shadow: inset 0 1px 1px rgba(0, 0, 0, 0.075), 0 0 8px rgba(82, 168, 236, 0.6);
    }
</style>